Previously, the wiping of pens in ink-jet printheads involved moving the printhead carriage to a position above the service station containing the wipers, raising the service station to a predetermined height of interference between the wiper tips and the pens and then moving the carriage across the stationery wiper tips. This often caused the wiper tips at the end of the wipe stroke uncontrollably to flick wet ink into the printer. It also frequently caused the resilient wiper to "pole-vault" at the beginning of the wipe stroke due to a reverse bias angle of the wiper as it contacted the pen and at the end of the wipe stroke due to reversal of the direction of carriage motion while the wiper was still in contact with the pen. Pole vaulting is undesirable also because it impacts the pen upwardly, potentially damaging the pen or the wiper or both. One previously proposed solution to the pole vault tendency has been to continue the wipe stroke all the way across the pen surface until it was clear of the pen before reversing the printhead carriage's direction. Unfortunately, this increases the lateral carriage travel and thus the width of the ink-jet printer's footprint, which is a critical parameter in many printer installations. It also virtually guarantees that wet ink will be flicked into recesses within the printer as the deflected, resilient wiper springs free of the pen.
Vertically reciprocable sleds mounting wipers for servicing ink-jet pens recently have been developed for use in ink-jet printers. One such sled subsystem is described in co-pending U.S. application Ser. No. 07/954,846, entitled "Printer Service Station", filed Sep. 30, 1992, of Gast et al., and subject to common ownership herewith. The disclosure of that patent application is incorporated herein by this reference.